Nongaussianity from Tachyonic Preheating in Hybrid Inflation

Abstract

In a previous work we showed that large nongaussianities and nonscale-invariant distortions in the CMB power spectrum can be generated in hybrid inflation models, due to the contributions of the tachyon (waterfall) field to the second order curvature perturbation. Here we clarify, correct, and extend those results. We show that large nongaussianity occurs only when the tachyon remains light throughout inflation, whereas n=4 contamination to the spectrum is the dominant effect when the tachyon is heavy. We find constraints on the parameters of warped-throat brane-antibrane inflation from nongaussianity. For F-term and D-term inflation models from supergravity, we obtain nontrivial constraints from the spectral distortion effect. We also establish that our analysis applies to complex tachyon fields.

16 pages, 2 figures. Comments added to introduction

References in corpus (27)

• Wilkinson Microwave Anisotropy Probe (WMAP) Three Year Results: Implications for Cosmology
• Observational Signatures and Non-Gaussianities of General Single Field Inflation
• Non-Gaussianities in two-field inflation
• Primordial trispectrum from inflation
• The Inflationary Trispectrum for Models with Large Non-Gaussianities
• Non-gaussianity from the second-order cosmological perturbation
• Non-Gaussianity from Preheating
• Constraints on Supersymmetric Models of Hybrid Inflation
• Non-Gaussianity from Instant and Tachyonic Preheating
• DBI Inflation in the Tip Region of a Warped Throat
• Nflation: non-gaussianity in the horizon-crossing approximation
• Curvature perturbation from symmetry breaking the end of inflation
• Non-Gaussian Inflationary Perturbations from the dS/CFT Correspondence
• Primordial Non-Gaussianity and Gravitational Waves: Observational Tests of Brane Inflation in String Theory
• Non-gaussianity for a Two Component Hybrid Model of Inflation
• Higher order contributions to the primordial non-gaussianity
• Observing the Geometry of Warped Compactification via Cosmic Inflation
• Supergravity Modification of D-term Hybrid Inflation: Solving the Cosmic String and Spectral Index Problems via a Right-Handed Sneutrino
• D-term inflation in non-minimal supergravity
• Non-Gaussianity in braneworld and tachyon inflation
• Cosmological constraints on string scale and coupling arising from tachyonic instability
• Coupling Hybrid Inflation to Moduli
• Enlarging the parameter space of standard hybrid inflation
• Generating the primordial curvature perturbations in preheating
• Cosmic D-Strings and Vortons in Supergravity
• "Semi-Realistic" F-term Inflation Model Building in Supergravity
• The Non-Gaussianity of Racetrack Inflation Models

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